<!DOCTYPE html>
<style>
#flexbox {
    display: flex;
    flex-flow: column;
    height: 300px;
    width: 200px;
}
#left {
    flex: 1;
    background-color: yellow;
    min-height: 0;
}
#content {
    flex: 5;
    border: 5px solid blue;
    min-height: 0;
}
#content > div {
    height: 350px;
    background-color: orange;
}
</style>
<div style="height: 60px"></div>
<div id="flexbox" dir="rtl">
<div id="left"></div>
<div id="content"><div></div></div>
